Conduit for corrosive fluids



Marhv 15, 1949. R. E. CHAPPELL ErAL 2,464,487

` l coNDUIT -Fon coRRos'IvE .FLUIDs Filed July 26, 1944- Poberf Cbcg'pell alzoabn?. earner'k Bru/evitata Patented Mai'.` l5, 1949 CONDUIT FOR CCRBOSIVE FLUIDS Robert E. Chappell. Clayton M. Beamer, and

ARalph B.

DUH, Baton mille, Ll

vStandard i] Development Company, a col'-V poration 'of Delaware Application July 26, 19,44,A Serial No. 546,691

4 claims. (cl. iss-c4) This invention relates to conduits for handling corrosive fluids and more particularly to piping for processing equipment for handling corrosive liquids.

The piping for processing equipment handling corrosive fluids hasbeen fabricated in the past from a variety of materials constructed so that an inner lining material protected to a consider-V able extent a casing which, in general, had to withstand the. main pressure. Materials of the inner lining include glass, hard rubber and fused which win permit the construction of piping involving only two materials.

vAs an example of the method of construction and ofthe piping of this invention, the illustration may be'taken of selecting lengths of 6" regular piping material, such as shown in the drawing and designated by the numeral I0.

Such piping permits of inter-connection by masses. Construction of this type has been found generally unsatisfactory for the handling of corrosive fluids underpressure and temperatures of between 250 F. and 400 F. In the case of glass and thefused materials,'a particular objection is in regard to the making vof fluid-tight joints in the connection of various lengths of piping. The present invention is concerned with overcoming such disadvantages and the fabrica?y tion of piping in which corrosive iiuids under relatively high temperatures and pressures may be satisfactorily and safely handled.

It has been found that if a-rigid,corrosionre sistant, micro-porous material such as structural carbon', porcelain or similar preparations be employed as an inner-lining material, the corrosive eiects of hot acid and similar uids are limited to the amounts of seepage through pores and cracks to the surrounding casing. The eilects of inltration of the corrosive fluids may be overcome by enclosing the micro-porous material ina non-rigid corrosion-resisting material such as lead. The setting of vthe micro-porous material covered with the corrosion-resistant lead into a casing has been effected by pushing the combination into a steel pipe of larger diameter so as to give a tight t, or by tting the combination into a split pipe and subsequently clamping. The connection between various lengths of such piping is made fluid-tight by having projecting portions of the lead coating of the micro-porous material overlap on to the flanges of the casing maf terial and thus compacting such 1ead.-material in making tight connection between the'flanges.v

In some cases the covering of the inner amorphous material' with the intermediate corrosioninner lining because of its limited resistance to corrosion and erosion and because of its tendency to bulge or buckle. Similarly the outer casing may be moderately corrosion-resistant material aanges. YThe inside or the'piping is uned with sheet lead I2 of at least V4" thickness. Inside of this liner porcelain piping Il of about 5%"v diameter is slipped and is cemented at the ends of the liner and between they liner 'and the lead lining with asphalt. Connection between various lengths of such piping is then made by bolting the flanges with lead to lead contact. Leakage -through the inner lining into the joint may not be completely obviated by such method of construction but the formation cfa illm of an insoluble lead salt prevents further seepage of acid material into any gap which remains in the joint.

The piping prepared according to the invention having an inner lining of structural carbon, ceramic ware or porcelain backed by steel or similar material has been found very satisfactory. The piping has a simplicity and ease of construc-l tion, togetherwith strength. Furthermore, the piping prepared according to this invention can be easily made a component part of equipment involving yother types of materials in order to obtain a fluid-tight seal. Connection by anges of various pieces of piping constructed according -to the invention has been found to give a uidtight seal without any longitudinal breaking. At the present time the piping is also advantageous on account of the ready availability of the three materials employed in its fabrication.

The piping constructed according to the invention has been found to withstand severe corrosive conditions and to bepartlcularly advantageous under high-pressure conditions when suitable selection of materials of construction has been made.

What is claimed is:

l. A conduit for handling corrosive uids under pressure comprising a rigid corrosion-resistant-micro-porous lining in a pressure-resisting` casing separated therefrom by a thin film of a corrosion-resistant metallic material, said thin film of corrosion-resistant4 metallic material at conduit ends also being ilanged'outwards over 4. A conduit for handling corrosive uids ,un-f Number der pressure according to claim 1 in whichthe 595,437 thin 111m of corrosion resistance metallic material 785,176 isflead. 895,412

ROBERT E. CHAPPELL. 5 930,927 CLAYTON M. BEAMER. 1,644,361 RALPH B. DUFF. 2,006,226

REFERENCES CITED The following references are of record in the 1 Number 111e of this patent: lg UNITED STATES PATENTS 331917 Number Name Date 686,441 33,152 Knight Aug. 27, 1861 1s 113,891 38,112 Knight Apr. 7, 1863 

